Paul St-Aubin edited section_Methodology_subsection_Site_Selection__.tex  almost 9 years ago

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In Sweden, four roundabouts were selected to complement the existing Québec data. These roundabouts were selected on the basis of similarity in geometric design and land use with typical Québec roundabouts. This typical design is characterised by a single lane (on the approach, exit, and ring, each), an approach speed limit of 50 km/h, an outside radius of 15-25 meters, very-low to medium urban density, suburban or commercial land use, moderate visibility over the centre island, and pedestrian crosswalks. Québec roundabout signalisation design is functionally identical to Swedish design, though differs in aesthetics. The Swedish roundabouts chosen were all located in the Skåne province, near the city of Lund.  One important distinction between the Québec and Swedish roundabouts are the pedestrian and, especially, cyclist flows. Cyclist flows in the Québec roundabouts are virtually non-existent; however these flows are non-trivial at many, but not all Swedish roundabouts. Consequently, only Swedish roundabouts with limited pedestrian or cyclist flows were considered for this study (low pedestrian and cyclist flows are still very common in Swedish roundabouts in low-density areas). It's also worth noting that besides aesthetic differences, the design of the Swedish roundabouts has one vital difference with Québec roundabouts: virtually all Swedish sidewalks integrate a cycle lane and it is not uncommon for these sidewalks to bypass roundabouts entirely via tunnels. However, because the movement of cyclists are mixed with pedestrians at crosswalks, interactions between motor-vehicles and cyclists are virtually identical to those between motor-vehicles and pedestrians. Cycling \textit{inside} \textit{within}  the roundabout is rare both in Québec and at the Swedish sites selected. Cyclists aversion to roundabout lanes might be attributed to higher accident rates and compounded by a lack of the safety-in-numbers effect \cite{Daniels_2010}  \subsection{Analysis Zone}